Gee-whiz science yields high res climate models

A climate scientist has used the powerful supercomputers at Berkeley Laboratory to carry out ‘gee-whiz science’, producing high resolution models predicting extreme storms caused by climate change. These models, developed using version 5.1 of the Community Atmospheric Model, developed by the Department of Energy (DOE) and the National Science Foundation (NSF), are not only better at reproducing intense storms than current models, but can do it much faster. Michael Wehner used the software to run a complete model in just three months. “I’ve been calling this a golden age for high-resolution climate modelling because these supercomputers are enabling us to do gee-whiz science in a way we haven’t been able to do before,” said Wehner, who was also a lead author for the recent Fifth Assessment Report of the Intergovernmental Panel on Climate Change. “These kinds of calculations have gone from basically intractable to heroic to now doable. I’ve literally waited my entire career to be able to do these simulations.” Wehner and colleagues, who published their results in the Journal of Advances in Modelling Earth Systems, analysed the period 1979 to 2005 at three spatial resolutions: 25km, 100km, and 200km and compared those results to each other and to observations. The higher resolution was particularly useful in modelling mountainous areas since the model can take an average of the altitude in the grid, which can enable scientists to better simulate snow and rain in the region. “High resolution gives us the ability to look at intense weather, like hurricanes,” said Kevin Reed, a researcher at the National Center for Atmospheric Research (NCAR). “It also gives us the ability to look at things locally at a lot higher fidelity. Simulations are much more realistic at any given place, especially if that place has a lot of topography.” The high-resolution model produced stronger storms and more of them, which was closer to the actual observations for most seasons. These high-resolution models will help scientists to better understand how climate change will affect extreme storms. http://youtu.be/cNyftYdjt-Q The effect of horizontal resolution on simulation quality in the Community Atmospheric Model, CAM5.1